Wheel dressing mechanism



Dec. 27, 1932. .1. EDGAR WHEEL DRESSING MECHANISM I Y Original FiledNov. 4. 1927 3 SheetsSheet 1 gain? 67501".-

IA'ITORNEYS Dec. 27, 1932. J.EDGAR 1,892,388

WHEEL DRESS ING MECHANISM Original Filed Nov. 4. 1927 5 Sheets-Sheet 2Dec. 27, 1932. D R 1,892,388

WHEEL DRESSING MECHANISM Original Filed Nov. 4.1927 8 Sheets-Sheet 8INVENTOR Jojm Ea? ar' ATTORNEYS Patented Dec. 27, 1932 UNITED STATESPATENT OFFICE JOHN EDGAR, OF ROCKFORD, ILLINOIS, ASSIGNOR TOBARBER-COLMAN. COMPANY, OF ROCKFORD, ILLINOIS, A CORPORATION OF ILLINOISWHEEL DRESSING MECHANISM Original application filed November 4, 1927,Serial No. 230,966. Divided and this application filed January 9,

v 1928. Serial N 0. 245,351.

The present invention relates to improvements in dressing mechanisms forgrinding wheels, and has particular reference to a novel dressingmechanism adapted to be incorporated in a grinding machine and'to auto--matically and periodically dress the grinding wheel in timed relationto the cyclic operation of the machine.

One of the objects of the present invention resides in the provision ofa new and improved dressing mechanismv for a grinding machine having aslide movable laterally of the grinding wheel, in which the dressingmechanism is supported on but is non-movable with the slide, and whichis operable through movement of the slide in one, direction to dress thegrinding wheel.

A further object resides in the provision in a grinding machine having awheel with a V-shaped cutting periphery, of a novel dressing mechanismhaving tools for operating on the inclined sides of the grinding wheeland a tool for operating on the periphery .of the grinding'wheel, saidtools serving to gradually change the form of the grinding wheel from ablunt contour into the desired predetermined contour, and to limit theposition and form of the grinding wheel upon a relative approach feedbetween the grinding wheel and the dressing mechanism.

, A further object resides inthe provision of a novel mechanism having apluralityof dressing tools adapted to be actuated in timed relation bymeans of asingle operating element to dress a plurality of separategrinding surfaces, and movable without interferencewith each other.

Other objects reside in the provision of a dressing mechanism of theabove character in which each of the dressing tools is independently'adjustable, which is simple and inexpensive in construction, and whichis positive and eflicient in operation.

A further object resides in the provision in a dressing mechanismhaving'a dressing tooland an actuating member therefor,of a clutch operativelyint sed between said tool and said member, clutch being operative uponmovement of said member in tion.

one direction and inoperative upon movement of said member in anotherdirection.

Further objects and advantages will become apparent as the descriptionproceeds.

In the accompanying drawings, Figure 1 is a fragmentary view partiallyin section of a grinding machine to which a dressing mechanism embodyingthe features of my invention has been applied, the front end of thedressing mechanism being shown in elevation.

Fig. 2 is a view similar to Fig. 1, but showing the dressing mechanismin rear eleva- Fig. 3 is the dressing mechanism taken along line 3-3 ofFig. l.

'Fig. 4 is a fragmentary view partially in section of the means foradjustably supporting the dressing tools.

Fig. 5 is a longitudinal sectional View of the clt ressing mechanismtaken along line 55 of Fig. 6 is a sectional view taken along line 66 ofFig. 5.

Fig. 7 is a sectional view taken along line 7-7 of Fig. 1. I v

Fig. 8 is a diagrammatic view showing the contour of the grinding wheelat difierent stages of the grinding operation.

While the invention is susceptible of various modifications andalternative constructions, I have shown in the drawings and will hereindescribe in detail the preferred embodiment but it is to be understoodthat I do not'thereby intend to limit the invention to the specific formdisclosed, but intend to cover all modifications andalternativeconstructions falling within the spirit and scope a fragmentary detailedview of ing machine comprises a base 10 having a vertical column 11. Ahead stock slide 12 which supports a grinding wheel 13 adapted to bedriven through a shaft 14, a pulley 15 and a belt 16, is adjustablymounted on the column 11. Preferably, this adjustment is provided byanon-rotatable feed screw 17 depending from the slide 12, and by arotatable nut 18 anchored in the column 11 and having a threadedengagement with the screw 17, said nut being adapted to be rotatedthrough any suitable means (not shown).

While the dressing mechanism may be adapted to operate on a largevariety of grinding Wheels, in the present instance, the grinding wheel13 is flat in form, and has a beveled or V-shaped grinding peripherycomprising oppositely inclined side faces 19 and 20, and a flatintermediate peripheral face 21, thus adapting the grinding wheel forgrindin V-shaped screw threads 22 (see Fig. 8).

ounted on the base 10 for movement toward and from the column 11perpendicular to the plane of the grinding wheel 13-is an indexing slide23. A traverse slide 24 adapted to support a work holder (not shown) ismounted on the index slide 23 for reciprocation in the plane of thegrinding wheel 13. While the specific means for actuating the slides 23and 24 is not disclosed herein, it will be understood that movement ofthe slide 24 carries the work across the grinding wheel 13 to grind thethreads 22 individually, and that movement of the slide 23 in oppositedirections serves respectively to index the threads 22 successively intogrinding position, and to return the work to the starting position forthe commencement of a deeper cut.

The dressing mechanism comprises a suitable base 25 mounted on the slide24 for long itudinal and lateral movement therewith.

he upper surface of the base 25 is formed with dove-tailed guides 26 onwhich a slide 27 is secured by suitable gib plates 28. The

slide 27 is rigidly secured against movement with the slide 23 laterallyof the base 10 by means of a rearwardly extendin arm 29 hav- I ing adepending finger 30 slida ly engaging in a spline groove 31 in the uppersurface of a block 32 secured across the front of the colum 11. By thisconstruction, the dressing mechanism is retained in the plane of thegrinding wheel 13 for movement into and out of operative position withthe slide 24 regardless of the lateral position of the slide 23."

Secured to the rear side of the slide 27 "is a depending V-shapedbracket 33 having: a bearing 34 at its apex in which a stub shaft 35 isrotatably mounted. The inner end of the shaft 35 has a collar 36 securedthereto, and abutting against'the end of the bearing 34, and isformedwith a spur gear 37 which meshes with a rack gear 38 suitably secured tothe underside of the base 25 and extending transversely thereof. Theouter end of the shaft 35 is formed with an enlargement 39 having aplurality of peripherally spaced and inclined notches or cam faces 40. Asuitable clutch sleeve 41 is rotatably mounted on the shaft 35 betweenthe adjacent end of the bearing34 and the enlargement 39, and has anannular flange 42 disposed about the periphery of said enlargement.

A plurality of balls 43, one in each instance, are freely disposed inthe notches and are retained therein by means of an end cap 44 fittingover the open end of the flange 42. It will be-noted that when the shaft35 is rotated in a clockwise direction as viewed in Fig. 6, as it iswhen the base'25 is moved forwardly from the column 11, the balls 43will move into wedging engagement with the notches 40 and the flange 42so as to effect a clutch connection between the shaft 35 and the sleeve41; and that when the shaft 35 is rotated in a counter-clockwisedirection, as it is when the base 25 is moved rearwardly toward thecolumn 11, it will. rotate freely without rotating the sleeve 41.

Keyed on the sleeve 41 is a spur gear 45 which meshes with a pinion 46k'eyed to a stub shaft 47 journaled in the bracket 33. The pinion 46 isformed integral on one end with an eccentric 48 which is rotatablydisposed in a bifurcated end 49 of a bell-crank lever 50 keyed to theouter end of a shaft 51 journaled in the slide 27 The shaft 51 extendsthrough the slide 27, and has an arm 52 secured to its front end. Asuitable dressing tool 53 is adjustably secured in a socket 54 in thefree end of the arm 52. In the present instance, the dressing tool 53has 9. diamond point 55, and is adapted to be adjusted by means of ascrew 56 threaded into the inner end of the socket 54. The diamond pointis arranged for oscillation in a vertical plane across the peripheralface 21 of the grinding wheel 13 to dress the latter.

One arm of the lever 50 is formed with a gear segment 57 which mesheswith a gear segment 58 rigidly secured to one end of a shaft 59. Thelatter is suitably journaled in a bearing' 60 formed in an upstandingbracket 61 at the rear edge of the slide 27. A spur car 62 is keyed tothe right end of the sha t 59, and meshes at opposite sides with, tworack gears '63 and 64' provided on suitable dressing tool slides 65 and66, re-

"Preferably, the gear racks 63 and 66, and extend longitudinally alongthe rear side edges thereof.

The slides 65 and.66 carry suitable dressing tools 67 and 68 havingdiamond points 69 and 70 adapted respectively to dress the cutting faces19 and 20 of the grinding wheel 13. Preferably, the dressingtools 67 and68 are mounted in suitable sockets 71 formed in laterally projectinglugs 72 and 73 on the ormedint'egral with the slides 65 right sides ofthe slides 65 and 66, and can be adjusted therein by means of suitableadjusting screws 74 and 7 5.

The slides 65 and 66 are mounted for reciprocation on suitable brackets76 and 77 adjustably secured to the bracket 61. In the present instance,each bracket 76-77 is provided with a guide strip 7 8 having V-shapedguideways 79 in opposite longitudinal edges. Each slide 6566 islongitudinally recessed in its rear face to form spaced flanges 80having V-shaped guideways 81 directly opposed to the guideways 7 9. Aplurality of balls 82 are disposed between the guideways 79 and 81.Preferably, the balls 82 are held in spaced relation in suitableretaining strips 83 which extend between the guideways 79 and 81, andthe ends of which are bent over the ends of the slides 66. The brackets7 6 and 77 are provided with arcuate arms 84 and 85 respectively, ofwhich the arm '84 is ad just'ably clamped to a plate 86 on the bracket61 by means of a bolt 87. The arm 85 is rigidly secured to the plate 86asby means of screws, and the two are secured to the bracket 61 by meansof a bolt 87. To this end, the arms 8485 are formed with T-slots 88respectively engaging the heads of the bolts 87.

It will be evident that as the base 25 is moved away from the column 11,the eccentric 48 will be rotated in a counterclockwise direction asviewed in Fig. 2. This will oscillate the shafts 51 and 59 toreciprocate the dressing points 556970 respectively across the grindingfaces 192021. The relative movement of the dressing points is so timedthat there is no interference. By adjusting the brackets 84 and 85 tothe proper angle, the desired contour will be provided on the grindingwheel. As the grinding wheel 13 is fed downwardly its contour willgradually approach the final predetermined contour, the dressing points55'697O serving to limit the depth and shapeof the cut. Thus, at thebeginning of the grinding op-' eration, see a in Fig. 8, the grindingwheel 13 is blunt, but cuts the full Width of the thread 22. As thegrinding wheel cuts deep- .er and deeper, see b and c in Fig. 8, itsform becomes more pointed. It will be evident that the grinding isperformed mainly by the extreme periphery of the wheel 13. The

dressing tool 55 limits the depth of the cut.

I claim as my invention: 1. A dressing mechanism having, 1n combination,a base, a support mounted for relative reciprocation or. said base, adressing tool movably mounted on said support, means for operating saiddressing tool, said means comprising a one direction clutch, one elementof said clutch being connected to a drive pinion, and arack gear on saidbase and in e'sfh-with said pinion, whereby said dressg t 001 will beoperated upon relative moveni'ent of said support on said base in one digear, said rack extending in the directionof relative movement of saidsupport, a clutch member on said shaft, a clutch sleeve on said shaft,coacting means between said clutch member and said clutch sleeve, saidlast mentioned means being effectual to drive said sleeve upon rotationof said shaft in one direction but being ineflectual to drive saidsleeve upon rotation of said shaft in the other direction, a wheeldressing element movably mounted on said support, and means operativelyconnecting said sleeve to said wheel dressing element for actuating thelatter upon rotation of said sleeve.

3. A dressing mechanism having, in combination, a base, a supportmounted for relative reciprocation on said base, a plurality of dressingtools movably mounted on said support, and means for operating saiddressing tools, said last mentioned means comprising a one directionclutch operably connected to said base to effect movementof said toolsupon relative movement of said support in one direction and to beineffectual upon relative movement of said support in the otherdirection on said base.

4. A dressing mechanism having, in combination, a base, a supportmounted for relative sliding movement on said base, a shaft journaled insaid support, a gear rack on said base, said rack extending in thedirection of relative movement of said support, gear means connectingsaid shaft to said rack, a clutch element on said shaft, a second clutchelement, coacting means between said clutch elements, said lastmentioned means being effectual to drive said second clutch element uponrotation of said shaft in one direction but being ineffectual to drivesaid second clutch element upon rotation of said'shaft in theotherdirection, a wheel dressing tool movably mounted on said support,and means operatively connecting said second'clutch element to saidwheel dressing tool,

5. A dressingmechanism comprising, in combination, a base, a supportmounted for relative reciprocation on said'base, a shaft rotatablymounted on said support, a dress 6. A dressing mechanism comprising, in

combination, a support, a pair of tool slides mounted for reciprocationon said support, said tool slides being angularly adjustable on saidsupport, a shaft in said support, gear means operatively connecting saidshaft to said slides, a second shaft, a laterally extending holderhaving a dressing tool mounted combination, a support, a pair of toolslides mounted for reciprocation on said support, said tool slides beingangularly adjustable on said support, a shaft in said support, gearmeans operatively connecting said shaft to said slides, a second shaftin said support, gear segments on said shafts in mesh with each other, alaterally extending holder having a dressing tool mounted on said secondshaft, one of said gear segments having a bifurcated arm, an eccentricdisposed in said bifurcated arm, and means for rotating said eccentric.

8. A dressing mechanism comprising, in combination, a support, a pair ofguides having bracket arms arcuately adjustable about a common center onsaid support, two slides mounted respectively on said guides, twodressing tools one operatively mounted on each slide, two longitudinalgear racks one on each slide, a gear disposed between and in mesh withsaid racks, said gear being rotatable on said center, a shaft forrotating said gear, and means for oscillating said shaft.

9. A dressing mechanism comprfsing, in combination, with a grindingwheel adapted to have a V-shaped contour and a support for the grindingwheel, a base reciprocable relative to said support in the plane of thegrinding wheel and also transversely of the grinding wheel, means foreffecting a feeding movement of said grinding wheel toward said base, adressing support transversely slidable on said base, means for holdingsaid support against movement relative to said first mentioned supporttransversely of said grinding wheel, a plurality of dressing toolsmounted on said dressing support in position respectively to dressopposite side faces and the peripheral face of said grinding wheel, andmeans operable through relative movement between said dressing supportand said base for actuating said dressing tools across the respectivefaces of said grinding wheel.

10. A dressing mechanism comprising, in combination, a support, ashaftrotatably mounted in said support, a gear segment on said shaft, meanssupporting a dressing tool 0nd shaft rotatably mounted in said support,a bifurcated arm on said second shaft, said arm having a gear segment inmesh with said first mentioned gear segment, means supportmg a dressingtool operatively connected to said second shaft, an eccentric journaledin said support and operatively disposed in said bifurcated arm, andmeans for rotating said pccantric whereby to oscillate said dressing 11.A dressing mechanism comprising, in

combination, a support having an annular ring with a concentric arcuateslot, a bracket having an a-rcuate arm, said arm having an arcuateprojection fitting in said slot for angular adjustment and having anarcuate T-slot opening laterally through said proection, means ooactingwith said T-slot for securing said arm in position of adjustment to saidring, said bracket having a guide, a slide reciprocable on said guide,anti-frict1on bearings disposed between said guide and said slide, gearmeans for reciprocating said slide and a dressing tool adjustablymounted on said slide.

12. A dressing mechanism comprising, in combination with a grindingwheel and a support for the grinding wheel, a base reciprocable relativeto said support transversely of the grinding Wheel axis. and alsoparallel to said axis, means for effecting a relative feeding of saidgrinding wheel toward said base, a dressing support relativelyoperatively connected to said shaft, a sec- In testimony whereof, I havehereunto affixed my signature.

